Monitoring agents with Legion Web

legion_web is a LiveView dashboard, packaged separately from Legion, that follows every agent live: prompts, generated snippets, and results, built on the telemetry events Legion already emits. It shows every user's conversations, so mount it behind authorization before you expose it.

Each conversation expands into its iterations, the Lua or Elixir it generated, and what came back from your tools. Without a store, the dashboard only shows agents still running in this node; add Legion.Store.Postgres (see Installation) to keep conversations around after an agent stops or the app restarts.

Install

mix hex.info legion_web

# mix.exs
{:legion, "~> 0.6"},
{:legion_web, "~> 0.5"}

mix deps.get

With :igniter in the project, mix legion_web.install adds the import and a /legion route behind :browser alone. Move that route into an authorized scope before you deploy, as below.

Mount it behind authorization

:browser plus a signed-in check is not enough: any signed-in user would read every other user's prompts and results. Put the route behind a pipeline that rejects non-admins, or, if the app has none, behind a dev-only block.

# lib/my_app_web/router.ex
import LegionWeb.Router

# admin-only scope - the pipeline must reject non-admins, and on_mount
# repeats the check on the LiveView socket
scope "/admin" do
  pipe_through [:browser, :require_admin]
  legion_dashboard "/legion", on_mount: [{MyAppWeb.UserAuth, :require_admin}]
end

# dev-only block, when the app has no admin pipeline
if Application.compile_env(:my_app, :dev_routes) do
  scope "/dev" do
    pipe_through :browser
    legion_dashboard "/legion"
  end
end

Run mix phx.server and visit the route you mounted.